Lavatory freshening and/or cleaning system and method

ABSTRACT

A lavatory freshening and/or cleaning system comprises a dispenser for dispensing a liquid composition from under the rim of a lavatory bowl. The dispenser is in the form of a reservoir arranged for suspension from the rim of lavatory bowl, and the reservoir contains the liquid composition. The liquid composition comprises a combination of anionic and non-ionic surfactants having a total concentration of 22.5 wt. %, a thickening agent having a concentration of 0.40 wt. % and a perfume having a concentration of 6.00 wt. % and having a viscosity of a bout 3,500 mPa s.

[0001] This invention relates to a freshener and/or cleaner system forthe lavatory and to a method of using such a system in a lavatory bowl.In particular, this invention relates to a system comprising a liquidfreshening and/or cleaning composition and a liquid dispenser.

[0002] Several lavatory freshening and/or cleaning systems are known.These systems include “solid block” type systems, where a fresheningand/or cleaning block is placed either under the rim of the lavatory orin the cistern. In the case of the under the rim system, water dissolvespart of the block each time the lavatory is flushed, allowing thelavatory bowl to be cleaned and/or freshened. In the case of the cisternblock system, part of the block dissolves in the cistern prior toflushing and the toilet is cleaned and freshened on flushing of thewater held in the cistern into the lavatory bowl. However, solid toiletblocks have demonstrated several drawbacks, in particular theirinability to deliver constant amounts of cleaning and freshening agentsduring the lifetime of the block.

[0003] Other freshening and cleaning systems are of theliquid-dispensing type. Such systems include a liquid dispenser and aliquid freshening and/or cleaning composition. A liquid dispensersuitable for such a system is disclosed in the applicant's publishedinternational patent application WO 99/66139. Such liquid dispensersgenerally comprise a reservoir and a liquid-conveying device in the formof a pad, or a plate having capillary channels formed therein, theliquid-conveying device and the reservoir being so connected as to allowthe freshening and/or cleaning composition held in the reservoir to betransferred to the liquid-conveying device in a controlled manner. Theliquid dispenser is positioned under the rim of a lavatory such that,during flushing, a sufficient amount of freshening and/or cleaningcomposition is transferred to the lavatory bowl to effect the cleaningof the bowl.

[0004] In order for liquid cleaning systems to be effective, the liquiddispenser must be provided with a suitable liquid cleaning and/orfreshening composition. It is desirable that such a liquid compositionpossess certain properties in order to carry out its freshening and/orcleaning functions. In particular, it is desirable that, when thecomposition is dispensed by flushing, sufficient foaming occurs. Foamingis desirable in order to promote cleaning of the lavatory bowl anddispersal of any perfume which is contained in the composition. Foamingalso confers certain aesthetic properties when the toilet is flushed.

[0005] A known liquid cleaning composition, stated to be suitable forliquid cleaning systems of the type hereinbefore described, is disclosedin European patent application EP-A-0 775 741, which describes acomposition having a viscosity at room temperature of 10 to 2 000 mPa sand comprising:

[0006] (a) 1 to 25 wt. % of perfume,

[0007] (b) 10 to 50 wt. % of anionic or non-ionic surfactant,

[0008] (c) 1 to 20 wt. % of non-evaporating, water soluble evaporationregulator, and

[0009] (d) balance solvent.

[0010] As used herein, the term “viscosity” refers to the dynamicviscosity, as measured using a Brookfield viscometer (spindle no. 3, 12rpm, 30 seconds at 20° C.). The above range of values for the viscosityis believed to be typically used for reasons of economy and ease ofmanufacture.

[0011] However, dispensers incorporating such liquids have been found,under certain circumstances, to draw the flushing water into thereservoir. This effect can lead to a reduction in the concentration ofthe active components in the liquid contained in the reservoir, andhence a corresponding reduction in the quantity of the active componentstransferred to the lavatory bowl, over the lifetime of the reservoir. Inparticular, this is manifested by reduced foaming and/or fragrancerelease.

[0012] The present inventors have discovered that, by substantiallyincreasing the viscosity of the liquid composition, these undesirableeffects can be reduced substantially, or even eliminated.

[0013] Thus, in accordance with the present invention, there is provideda lavatory freshening and/or cleaning system comprising a dispenser fordispensing a liquid composition from under the rim of a lavatory bowl,said liquid composition having a viscosity greater than 2 500 mPa s.

[0014] The viscosity is preferably less than 6 000 mPa s and morepreferably within the range 3 000 to 5 000 mPa s. The most preferredvalue is about 3 500 mPa s.

[0015] Typically, such liquid compositions would include surfactants.Surfactants carry out a variety of functions, inter alia, generating offoam during the flush and dissolving or micro-emulsifying any perfumepresent in the liquid composition.

[0016] Preferably, the total surfactant concentration is within therange 5 to 35 wt. %, the most preferred value being substantially 22.5wt. %.

[0017] Suitable surfactants are anionic and/or non-ionic surfactants,although a combination of anionic and non-ionic surfactants isparticularly desirable. The preferred anionic surfactant is an alkylether sulphate, such at that marketed under the trade name Steol CS 270,containing active surfactant at a concentration of 70 wt. %, and thepreferred non-ionic surfactant is an ethoxylated synthetic alcohol, suchas that marketed under the trade name Lutensol AO8.

[0018] Optionally, perfume may be present to provide freshening of thelavatory bowl and its vicinity. A suitable perfume for the liquidcomposition is that marketed under the trade name Vertana 114.737.

[0019] The preferred total concentration of perfume is within the range4 to 15 wt. %, the most preferred value being substantially 6 wt. %.

[0020] Although the combination of surfactant and perfume can act as athickening agent, and thus the viscosity of the composition may becontrolled to an extent by the choice of surfactants and/or perfume, thecomposition preferably includes one or more additional thickeningagents, having a preferred total concentration within the range 0.2 to20 wt %. The most preferred concentration of additional thickening agentis substantially 0.40 wt %. A suitable thickening agent is ahydroethylcellulose such as that marketed under the trade name Natrasol250 HHR.

[0021] In addition, humectants may be present in the liquid composition.Humectants are desirable when a perfume is present, in order to regulatethe evaporation of the perfume from the composition. Additionally,humectants are useful in preventing phase separation of, andprecipitation from, the composition.

[0022] Suitable humectants include glycols, glycoethers, alcohols,sugars and polyethers.

[0023] Optionally, the composition may comprise sequestrants, pH controlagents, dyes and preservatives.

[0024] The invention extends to a method of use of such a lavatoryfreshening and/or cleaning system in a lavatory bowl.

[0025] A preferred embodiment of the present invention incorporates aliquid composition having the following components: Weight Componentpercent Common name Chemical name type Function Water Water Solvent 25Steol CS 270 Sodium Lauryl Anionic Perfume (containing Ether Sulphatesurfactant solublisation, 70% active form surfactant) generation andviscosity building 5.0 Lutensol AO8 Non-ionic Perfume surfactantsolublisation, form generation and viscosity building 7.00 DipropyleneShort-chain Humectant Glycol hydrocarbon 2.00 Dequest 2010 PhosphonateSequestrant 1.60 Sodium Control of pH Hydroxide (32 wt. % aqueoussolution) 0.40 Natrasol 250 Cellulosic Thickener HHR 0.005 Dye 6.00Perfume 0.02 Myacide BT Preservative

[0026] As can be seen from the above table, the composition comprisesSteol CS 270. This includes an anionic surfactant at a concentration of70 wt. %, so that the actual concentration of anionic surfactant in thecomposition is 17.5 wt. %, resulting in a total surfactant concentrationin the composition of 22.5 wt. %.

[0027] The resulting viscosity of the above liquid composition is about3 500 mPa s.

1. A lavatory freshening and/or cleaning system comprising a dispenserfor dispensing a liquid composition from under the rim of a lavatorybowl, said liquid composition having a viscosity greater than 2 500 mPas.
 2. A system as claimed in claim 1, wherein said liquid compositionhas a viscosity less than 6 000 mPa s.
 3. A system as claimed in claim2, wherein said liquid composition has a viscosity within the range 3000 to 5 000 mPa s.
 4. A system as claimed in claim 3, wherein saidliquid composition has a viscosity of about 3 500 mPa s.
 5. A system asclaimed in any preceding claim, wherein said liquid compositioncomprises a surfactant.
 6. A system as claimed in claim 5, wherein thetotal surfactant concentration is within the range 5 to 35 wt. %.
 7. Asystem as claimed in claim 6, wherein the total surfactant concentrationis substantially 22.5 wt. %.
 8. A system as claimed in any one of claims5 to 7, wherein said surfactant is either an anionic surfactant or anon-ionic surfactant or a combination thereof.
 9. A system as claimed inclaim 8, comprising an alkyl ether sulphate constituting at least oneanionic surfactant.
 10. A system as claimed in claim 8 or claim 9,comprising an ethoxylated synthetic alcohol constituting at least onenon-ionic surfactant.
 11. A system as claimed in any preceding claim,wherein said liquid composition further comprises perfume.
 12. A systemas claimed in claim 11, wherein the total perfume concentration iswithin the range 4 to 15 wt. %.
 13. A system as claimed in claim 11 orclaim 12, wherein the total perfume concentration is substantially 6 wt.%.
 14. A system as claimed in any preceding claim, wherein said liquidcomposition comprises a thickening agent.
 15. A system as claimed inclaim 14, wherein the concentration of thickening agent, apart from anysurfactant and perfume which may be present, is within the range 0.2 to5 wt. %.
 16. A system as claimed in claim 14 or claim 15, wherein saidthickening agent is a hydroxyethylcellulose.
 17. A system as claimed inany preceding claim, wherein said liquid composition further comprisesone or more of sequestrants, pH control agents, dyes and preservatives.18. A method of using in a lavatory bowl a lavatory freshening and/orcleaning system as claimed in any preceding claim
 19. A lavatoryfreshening and/or cleaning system comprising a dispenser for dispensinga liquid composition from under the rim of a lavatory bowl,substantially as hereinbefore described.
 20. A method of using in alavatory bowl a lavatory freshening and/or cleaning system substantiallyas hereinbefore described.